CN211088400U

CN211088400U - Composite structure of diffusion layer of separator flow channel and fuel cell using same

Info

Publication number: CN211088400U
Application number: CN201921989783.5U
Authority: CN
Inventors: 范冬琪; 曹寅亮; 孙健; 俞海蛟; 徐乃涛; 李文; 徐淳川; 徐鹏杰; 林滨; 赵海敏; 刘建国; 倪淮生; 陈会翠
Original assignee: Tianneng Battery Group Co Ltd
Current assignee: Tianneng Battery Group Co Ltd
Priority date: 2019-11-18
Filing date: 2019-11-18
Publication date: 2020-07-24
Anticipated expiration: 2029-11-18

Abstract

The utility model discloses a baffle runner diffusion layer composite construction and use fuel cell of this structure, wherein, baffle runner diffusion layer composite construction includes baffle, diffusion layer and sets up the runner layer between baffle and diffusion layer, the runner layer is cut off by interval arrangement's strip and is constituteed, constitutes the runner that the gas passes through between the adjacent wall, the strip cut off and adopt electrically conductive porous material to prepare. By adopting the structure, the fuel cell structure can be thinner, the processing is more convenient, and the volume ratio power density is higher.

Description

Composite structure of diffusion layer of separator flow channel and fuel cell using same

Technical Field

The utility model belongs to the technical field of fuel cell, especially, relate to a baffle runner diffusion layer composite construction and use fuel cell of this structure.

Background

A fuel cell is a device that directly converts chemical energy of hydrogen and oxygen into electrical energy through an electrode reaction. A fuel cell is typically constructed of a plurality of cell modules, each of which includes two electrodes (anode and cathode) separated by an electrolyte element and assembled in series with each other to form a fuel cell stack. By supplying each electrode with the appropriate reactants, i.e. supplying one electrode with fuel and the other with oxidant, an electrochemical reaction is achieved, resulting in a potential difference between the electrodes and thus the generation of electrical energy.

The bipolar plate is one of the key components of the fuel cell, and comprises an anode flow field plate and a cathode flow field plate, wherein the anode flow field plate is provided with a plurality of fuel gas channels which are arranged at intervals, the cathode flow field plate is provided with a plurality of oxidant gas channels which are arranged at intervals, hydrogen supplied to the fuel gas channels and air supplied to the oxidant gas channels react in a cathode gas diffusion layer in the PEMFC to form product water, and the product water in the cathode gas diffusion layer is discharged to the oxidant gas channels and is discharged out of the oxidant gas channels under the purging effect of redundant air in the oxidant gas channels.

Chinese patent publication No. CN101789511A discloses a membrane electrode assembly with an integrated flow field structure and a fuel cell thereof, wherein the membrane electrode assembly comprises two gas guiding layers, two gas diffusion layers, two catalyst layers and a proton exchange membrane layer, wherein the two catalyst layers are disposed on the proton exchange membrane layer to form an intermediate layer, the two gas diffusion layers are respectively connected with the intermediate layer and disposed at two sides of the intermediate layer, and the two gas guiding layers are respectively connected with the two gas diffusion layers.

Although the gas diversion layer is arranged in the technical scheme, the structure of the bipolar plate is simplified, the processing mode is more complex, and the thickness of the gas diversion layer is difficult to further reduce.

SUMMERY OF THE UTILITY MODEL

For solving the above-mentioned problem that prior art exists, the utility model provides a fuel cell of baffle runner diffusion layer composite construction and use this structure can make the fuel cell structure thinner, has higher volume ratio power density.

The technical scheme of the utility model as follows:

the utility model provides a baffle runner diffusion layer composite construction, includes baffle, diffusion layer and sets up the runner layer between baffle and diffusion layer, the runner layer comprises interval arrangement's strip wall, constitutes the runner that the gas passes through between the adjacent wall, the strip wall adopt electrically conductive porous material preparation.

The utility model discloses in, the runner layer can be formed by electrically conductive porous material blanking processing, and processing is convenient, under the condition of the same runner degree of depth, can make the thickness on runner layer littleer, makes overall structure thinner.

The material of the flow channel layer is the same as that of the diffusion layer, and the flow channel layer and the diffusion layer are both made of carbon fiber felt or carbon paper, so that the contact resistance between the flow channel layer and the diffusion layer is small.

The thickness of the separator is 0.8-1.2 mm, and a carbon plate or an anti-corrosion coating metal plate is adopted.

The flow channel layer is of an integral structure or a multi-piece structure. Wherein integrative structure can directly place between baffle and diffusion layer after fixing a position, and the multichip structure need use electrically conductive glue to install again on the baffle, and this kind of structure processing is convenient, adopts the cutting die just can produce, has saved stamping die, equipment investment such as engraving machine to cut off between the runner also has porous material to carry out the material exchange.

And a sealing gasket is arranged on the outer ring of the flow channel layer.

The utility model also provides an use above-mentioned baffle runner diffusion layer composite construction's fuel cell, form by a plurality of monocell module pile, every monocell module includes two baffle runner diffusion layer composite construction and sets up the CCM membrane between two diffusion layers.

Each single cell module is connected and bonded by an integrally formed rubber or silica gel sealing protection outer frame.

Compared with the prior art, the utility model discloses following beneficial effect has:

1. the utility model discloses a flow channel that easily blanking's slice conducting material such as carbon fiber felt or carbon paper blanked into the bipolar plate cuts off, forms composite construction with diffusion barrier, metal baffle, and processing is more simple and convenient, and under the condition of the same runner degree of depth, whole thickness is littleer, has improved volume ratio power density.

2. The utility model discloses in, the wall between each runner of runner layer that carbon fiber felt or carbon paper constitute also forms certain air current exchange by porous material, is favorable to the inside gaseous evenly distributed of polar plate.

Drawings

Fig. 1 is a solid diagram of the overall structure of a single battery module according to the present invention;

fig. 2 is a schematic cross-sectional view of a single cell module according to the present invention;

FIG. 3 is a schematic view of a gas flow in a prior art flow channel cut in a separator plate;

fig. 4 is a schematic view of the gas flow of the structure of the present invention.

Detailed Description

The invention will be described in further detail with reference to the following figures and examples, which are intended to facilitate the understanding of the invention without limiting it.

As shown in fig. 1 and 2, a composite structure of a separator flow channel diffusion layer is divided into a cathode portion and an anode portion, the cathode portion includes a cathode separator 1, a cathode gasket 2, a cathode flow channel layer 3a, a cathode diffusion layer 3b, and the anode portion includes an anode diffusion layer 5a, an anode flow channel layer 5b, an anode gasket 6, and an anode separator 7. The cathode flow channel layer 3a and the anode flow channel layer 5b are formed by punching carbon fiber felt or carbon paper or other conductive porous materials into an integral or multi-piece structure.

Wherein, a body structure can directly place between baffle and diffusion layer after fixing a position, and the multichip structure need use electrically conductive gluing to install again on the baffle, and this kind of structure processing is convenient, adopts the cutting die just can produce, has saved stamping die, equipment investment such as engraver to cut off between the runner also has porous material to carry out the material exchange.

The embodiment also provides a fuel cell adopting the separator flow channel diffusion layer composite structure, the fuel cell is formed by a plurality of single cell module galvanic piles, and each single cell module comprises two separator flow channel diffusion layer composite structures and a CCM (continuous current module) membrane 4 arranged between two diffusion layers. Each single cell module is connected and bonded by an integrally formed rubber or silica gel sealing protection outer frame, so that the disassembly and the assembly of the electric pile are more convenient and safer.

As shown in fig. 2, the cathode flow channel layer 3a is composed of strip-shaped partitions 9 arranged at intervals, and a flow channel 8 for gas to pass through is formed between adjacent partitions. The anode flow channel layer 5b is composed of strip partitions 11 arranged at intervals, and a flow channel 10 for gas to pass through is formed between the adjacent partitions.

The traditional partition generally adopts a mode of cutting flow channels on the partition plate, the gas flow direction of the traditional partition is shown in fig. 3, compared with the traditional partition mode, in the application, the partition between the flow channels of the flow channel layer formed by the carbon fiber felt or the carbon paper also forms certain gas flow exchange by the porous material, which is more beneficial to the uniform distribution of gas inside the polar plate, and the specific flow mode is shown in fig. 4.

In the utility model, the material of the flow channel layer is consistent with that of the diffusion layer, and the contact resistance is small; the carbon fiber surface felt is small in thickness, so that the volume of a fuel cell stack is effectively reduced, and the volume power density is improved; the carbon fiber is light in weight, so that the mass power density of the pile can be effectively improved; the composite structure has higher corrosion resistance and lower production research and development cost compared with a metal bipolar plate galvanic pile, and has higher strength and lower production cost compared with a graphite plate; the integrated single cell structure is convenient to disassemble, assemble and maintain, and improves the product safety.

The above-mentioned embodiment is to the technical solution and the beneficial effects of the present invention have been described in detail, it should be understood that the above is only the specific embodiment of the present invention, not used for limiting the present invention, any modification, supplement and equivalent replacement made within the principle scope of the present invention should be included in the protection scope of the present invention.

Claims

1. The utility model provides a baffle runner diffusion layer composite construction which characterized in that, includes baffle, diffusion layer and sets up the runner layer between baffle and diffusion layer, the runner layer comprises interval arrangement's strip wall, constitutes the runner that the gas passes through between the adjacent wall, the strip wall adopt electrically conductive porous material preparation.

2. The separator flow channel diffusion layer composite structure of claim 1 wherein said flow channel layer and diffusion layer are of the same material and are either carbon fiber felt or carbon paper.

3. The composite structure of the diffusion layer of the separator flow channel according to claim 1, wherein the thickness of the separator is 0.8-1.2 mm, and a carbon plate or an anti-corrosion plating metal plate is adopted.

4. The separator flow channel diffusion layer composite of claim 1 wherein said flow channel layer is a unitary or multi-piece structure.

5. The separator plate flow channel diffusion layer composite structure of claim 1 wherein said outer perimeter of said flow channel layer is provided with a gasket.

6. A fuel cell comprising the separator flow channel diffusion layer composite structure according to any one of claims 1 to 5, wherein a plurality of unit cell modules are stacked, each unit cell module comprising two separator flow channel diffusion layer composite structures and a CCM membrane disposed between two diffusion layers.

7. The fuel cell according to claim 6, wherein each unit cell module is connected and bonded by an integrally molded rubber or silicone sealing protective outer frame.